An additional 50 people have been sickened by the same salmonella “Saintpaul” infection in Arizona, California, Colorado, Connecticut, Idaho, Illinois, Indiana, Kansas, Oklahoma, Oregon, Utah, Virginia, Washington and Wisconsin, the federal Centers for Disease Control and Prevention reported.

Investigators are trying to determine whether raw tomatoes also are responsible for the illnesses in those states, said Arleen Porcell, a CDC spokeswoman.

The source of the tomatoes responsible for the illnesses has not been pinpointed, but health officials in Texas and New Mexico said none of them was grown in those two states.

At least 23 people have been hospitalized, and no deaths have been reported, she said. Patients ranged in age from 1 to 82.

The rarity of the Saintpaul strain and the number of illnesses “suggest that implicated tomatoes are distributed throughout the country,” she said. Interviews conducted with 73 people found the illnesses began between April 16 and May 27, Ms. Porcell said.

Cherry tomatoes, grape tomatoes, tomatoes sold with the vine still attached and homegrown tomatoes are likely not the source of the outbreak, Ms. Busemeyer said.

Also not associated with the outbreak are raw Roma, red plum and round red tomatoes from Arkansas, California, Georgia, North Carolina, South Carolina, Tennessee, Texas, Belgium, Canada, the Dominican Republic, Guatemala, Israel, Netherlands and Puerto Rico, according to the U.S. Food and Drug Association.

Salmonella is a bacteria that lives in the intestinal tracts of humans and other animals. It usually is transmitted to humans by eating food contaminated with animal feces.

Most infected people suffer fever, diarrhea and abdominal cramps starting 12 to 72 hours after infection. The illness tends to last four to seven days. Many people recover without treatment, but severe infection and death are possible.